Heated adhesive applicator roll system

ABSTRACT

The adhesive roll of a single facer machine and/or the adhesive rolls of a glue machine at a double facer are heated to a surface temperature of between 130* F and 150*F by circulating water to heat the starch adhesive to a temperature just below its gelatinization temperature so long as the rolls are rotating.

United States Patent Norman 1451 Dec. 19, 1972 [72] Inventor:

[73] Assignee: l-larris-Intertype.

Cleveland, Ohio [221 Filed: May 20,1970

21] App1.N0.: 38,950

Corporation,

[52] U.S. Cl. ..118/5, 165/89,165/107, 118/202, 165/134, 156/210, 156/499,

[51] Int. Cl. ..B05c 11/00, F281 5/02 Field of Search ....165/89, 90, 107; 34/124, 119; 126/113; 122/401; 118/60, 202, 5;156/578,

Charles R. Norman, Willingboro,

3,202,532 8/1965 Labombarde ..118/202 X 2,483,021 9/1949 Oaks ....165/l07 X 3,486,474 12/1969 Kosrow et aL. ....165/107 X 1,610,709 12/1926 Roberts 122/401 X 2,849,951 9/1958 Heinrich ..165/89 X 2,050,382 8/1936 Rowbotham et al ..118/60 X 2,254,390 9/1941 Olcott ....165/107 X 2,914,806 12/1959 Long et ul ..165/107 X FOREIGN PATENTS OR APPLICATIONS 778,232 7/1957 Great Britain ..34/124 Primary Examiner-Albert W, Davis, Jr. Att0rney-Seidel, Gonda & Goldhammer [57] ABSTRACT The adhesive roll of a single facer machine and/or the adhesive rolls of a glue machine at a double facer are 499 heated to a surface temperature of between 130F and [56] References Cited 150F by circulating water to heat the starch adhesive to a temperature just below its gelatinization tempera- UNITED STATES PATENTS ture so long as the rolls are rotating.

2,290,200 7/1942 Murch et al. ..118/202 X 7 Claims, 6 Drawing Figures z i I I F 24 62 l 32 L 46 38 4 6 4- a J I T n 44 40 47 PATENTEU 19 i973 3.706.298

SHEU 2 BF 2 mo /50 200 6 TEMPERATURE F O INVENTOR CHARLES R. NORMA/V ATTORNEYS HEATED ADHESIVE APPLICATOR ROLL SYSTEM This invention relates to a heated adhesive roll system which is adaptable for use at a single facer corrugated paperboard machine and/or a glue machine at the double facer. Each of these machines includes an adhesive applicator roll in contact with a source of starch adhesive. For many years, it was conventional to maintain thetemperature of the starch in the pan at ambient temperature or at a temperature approximately 100F. The conventional starch adhesive gelatinizes at a temperature of approximately l45-l55F and thereby becomes tacky so that it may act as an adhesive.

The additional heat required to increase the temperature of the adhesive while on the flute tips up to its gelatinization temperature at a single facer was normally attained by liner preheater rolls and a heated pressure roll. These rollsmay heat the liner to a temperature of 200F and higher. A double facer is normally provided with steam heatedchests which provide the necessary heat to raise the temperature of the adhesive while on the flute tips up to its gelatinization temperature.

The heating of the adhesive applicator roll so as to preheat the adhesive to a temperature just below its gelatinization temperature, that is, within 20 of its gelatinization temperature, provides a significant number of advantages. At the single facer, little or no preheating of the liner is required and the high nip forces common heretofore may be substantially reduced. This excessive nip loading has resulted in pressure roll marks on the surface of the liner. The rate of production of paperboard may be substantially increased by as much as fifty percent since the adhesive need only be raised in temperature by to in order to effect gelatinization.

Other advantages include substantially reducing the amount of heat required at the double facer whereby the double facer may be shorter, require less steam pressure, and steam chests maybe made to less stringent requirements as pertains to size and strength. Further, there is a reduced water loss by the adhesive into the paperboard. The lesser amount of water loss materially contributes to forming more uniform paperboard having a lesser tendency to exhibit warp. In addition, the rate of production of double wall and triple wall board may be increased as much as percent.

The system of the present invention continuously circulates hot water through the applicatorroll or rolls so long as the roll or rolls are being rotated. Water from the rolls is delivered to a surge tank. From the surge tank, the water is pumped through a heat exchanger and returned to the inlet side of the applicator rolls.

- The temperature of the water after it exits the heat exchanger is detected and utilized to control the inlet of steam into the heat exchanger.

The applicator rolls are preferably made with a baffle so as to direct the incoming water directly toward the inner periphery of the applicator roll. The baffle is preferably in the form of a sealed hollow member having tapered ends spaced from the I.D. of the applicator roll by webs or ribs. In this manner, the hot water cannot move in a direct line from the inlet to the outlet of the applicator rolls.

The system of the present invention is preferably constructed as a packaged unit mounted on a common support for installation as a unit on the corrugator machine bridge or other convenient support adjacent the applicator rolls.

It is an object of the present invention to provide a heated adhesive roll system.

It is another object of the present invention to provide a water circulation system for maintaining the surface temperature of applicator rolls at a predetermined level below the gelatinization temperature of starch adhesives so long as the rolls continue to rotate.

It is another object of the present invention to provide a water circulation heating system for adhesive applicator rolls of paperboard machinery wherein the system is packaged as a unit for installation on such machinery.

It is another object of the present invention to provide a heated adhesive roll water circulation system forpreferred; it being understood, however, that this invention is not limited to the precise arrangements and instrumentalities shown.

FIG. 1 is a diagrammatic illustration of the heated adhesive roll system of the present invention.

FIG. 2 is a schematic illustration of another embodiment of the system shown in FIG. 1.

FIG. 3 is a front elevation view' of the system shown in FIG. 2.

. FIG. 4 is a side elevation view of the structure shown in FIG. 3 as seen from the left side.

FIG. 5 is a schematic illustration of an adhesive roll in association with a glue pan.

FIG. 6 is a graph wherein the starch adhesive temperature is plotted against its viscosity in pound per feet per hour.

Referring to the drawing in detail, wherein like numerals indicate like elements, there is shown in FIG. I a heated adhesive roll system in accordance with the present invention designated generally as 10. The system 10 is particularly adapted for use in conjunction with an adhesive applicator roll 12 which may be the applicator roll of a single facer and/or glue machine. The roll 12 is provided internally with a deflector l4. Deflector 14 is preferably a sealed hollow structure having tapered ends and internally supported from the inner surface of the roll 12 by means of spaced ribs 16. Deflector l4 directs the incoming water from inlet conduit 18 along the inner peripheral surface of the applicator roll 12 so that it cannot flow on a direct line to the outlet conduit 20.

The outlet conduit 20 is provided with a strainer 22 and is connected to a surge tank 24. Surge tank 24 may be provided with a supply tank 26 connected thereby by a control valve 28. Supply tank 26 may contain a boiler compound, an antifreeze compound, or any other anticorrosive compound which may be periodically introduced into the surge tank by way of the intermittently operated valve 28. Valve 28 may be a time clock operated valve. 4

The surge tank 24 is provided with an overflow drain conduit 30. The outlet conduit 32 from surge tank 24 is connected to the inlet side of a pump 34 which pumps the water through a heat exchanger 36. The outlet of heat exchanger 36 is connected to one end of conduit 18.

Said one end of conduit 18 is provided with a temperature gauge 38 and a temperature sensor 40. Steam from a steam source 42 is introduced into the heat exchanger 36 by way of conduit 46. Conduit 46 is provided with an outlet pressure regulator 44 and a pilotoperated valve 48. Valve 48 is controlled by the temperature sensor 40 so that the temperature of the water in conduit 18 controls the introduction of steam into the heat exchanger 36.

The steam supply conduit 46 may be provided with a filter and a conventional pressure relief valve. Condensate collected in the heat exchanger 36 is pumped by way of conduit'52 and pump 54 to the surge tank 24. Operation of pump 54 may be controlled by the level of condensate within the heat exchanger 36 if desired.

Pump 34 is'connected to a source of electrical potential 56 by way of conductors containing a relay 58 and an on-off switch 60. The relay S8'is controlled by a motor 62 which rotatably drives the applicator 12 about its longitudinal axis. So long as motor 62 is rotating the applicator roll 12, the pump 34 will remain operating so that water will be continuously circulated through the applicator roll 12. When the motor 62 stops, the pump 34 will stop unless an idler motor is provided to continue rotating the applicator roll and the pump.

When the pump 34 stops, the temperature of the water within conduit 18 will rise to the point whereby sensor 40 will shut off valve 48. If desired, steam conduit 46 may be provided with a pressure gauge 47.

In FIG. 2, there is illustrated another embodiment of the present invention designated generally as The system 10' is particularly adapted for use at a double deck glue machine of a double facer. The system 10 is the same as system 10 with the following additional structure.

An adhesive applicator roll 64 is provided parallel to roll 12. Roll 64 has an inlet conduit 66 and an outlet conduit 68. Conduit 68 is connected to conduit 20. A branch conduit 70 extends from conduit 32 and is connected to the inlet side of a pump 72. The outlet of pump 72 is connected to the inlet side of heat exchanger 74. The outlet of heat exchanger 74 is connected to the inlet of conduit 66.

A branch conduit 76 extends from the steam supply conduit 46 to the heat exchanger 74. The temperature sensor 80 in conduit 66 controls valve 78 in conduit 76 for controlling the introduction of steam into the heat exchanger 74. A branch conduit 82 extends from the heat exchanger 74 to conduit 52 so that condensate may be pumped from heat exchanger 74 by way of pump 54 to the surge tank 24. The motor 62 is coupled to each of the rolls 12 and 64 for rotatably driving the same.

In FIGS. 3 and 4, there is illustrated the system 10' as a packaged unit for installation on the corrugator bridge of a glue machine of a double facer. As shown more clearly in FIG. 4, a structural member 84 is provided on the bridge for attaching the packaged unit. Member 84 is connected to a troughlike frame designated generally as 86 and having an upwardly and outwardly directed front wall 88.

The front wall 88 conveniently supports the temperature gauge for the circulation of water to roll 12,the steam pressure gauge 47, and the gauge 90 which indicates the temperature of the water circulating through the roll 64. All of said gauges are positioned so that they may be read by an operator standing at floor level and looking up at the same.

The support frame includes an upright rear wall 96. The heat exchangers 36 and 74 are interconnected with the front wall 88 and rear wall 96 by spaced braces 98. An electrical supply box 100 is supported by the wall 96. As shown more clearly in FIG. 4, the parallelism of the water circulation paths diagrammatically illustrated in FIG. 2 is maintained in the packaged unit illustrated in FIGS. 3 and 4. If desired, conduit.52 may be provided with a steam trap 102 and the steam supply conduit 46 may be provided with a safety valve 104.

The adhesive applicator rolls are adapted to be in contact with the adhesive which in turn is supported in a pan. This is diagrammatically illustrated in FIG. 5 and is conventional in the art. The adhesive roll 12in FIG. 5 is in contact with the adhesive 108 supported by the pan 106. A doctor roll 110 may be utilized for cooperation with the surface of the applicator roll 12.

The surface of the doctor roll 110 is spaced from the surface of the applicator roll by a distance of 0.005 to 0.016 inches. The roll 110 is preferably hollow and chilled to a temperature of about 50 to 60F to cause moisture to condense on its chrome-plated surface. The moisture creates a water slice which keeps the surface of the applicator roll substantially free of adhesive. Chilling of roll 110 can be accomplished by circulating tap water therethrough. The direction of rotation is shown in FIG. 5.

In FIG. 6, there is illustrated a graph of adhesive temperature versus the adhesive viscosity in pound per feet per hour. The graph is based on atypical cornstarch ad hesive having a gelatinization temperature of l45F. It will be noted that the viscosity of the adhesive is at a maximum at the gelatinization temperature. The curve indicates that up to a temperature of about 130F, very little change in viscosity takes place. It is possible, therefore, to preheat the starch from the conventional temperature of about F to an optimum temperature of about 5F below its gelatinization temperature. Thereafter, while the adhesive is on the flute tips, it need only be increased in temperature five degrees in order to effect gelatinization and a resultant bond.

Depending upon the material from which the applicator rolls are made, it may be desirable to provide the inner surface of the applicator rolls with an anticorrosive coating suchas a bronze coating, chrome plating, a galvanized surface, etc. The system of the present invention may be applied to applicator rolls in the field on existing machinery except for the baffle 14 which must be assembled within a new applicator roll as the roll is being constructed.

It will be noted that the water circulation system is a closed system wherein the water is. continuously used. The use of a surge chamber eliminates pressurization of the system which could cause air pockets or other high pressure problems with the circulation system such as reduction of heat transfer through the applicator roll.

In each of the, systems 10 and 10', the pump or pumps are operative so long as the applicator rolls 12 and/or 64 are being rotated. This arrangement prevents the rolls from being subjected to uneven heat expansion with subsequent out-of-roundness which can occur if the hot water circulates through stationary rolls. In system the motor for rotating the rolls is electrically coupled to the double facer or glue machine idling motor for simultaneous operation.

The present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof and, accordingly, reference should be made to the appended claims, rather than to the foregoing specification as indicating the scope of the invention.

lclaim:

1. A system for applying a starch adhesive bonding agent in a paperboard corrugator comprising at least one hollow adhesive applicator roll having an inlet and an outlet, means adjacent the roll for supporting the bonding agent, a closed circulation system for circulating heated water under pressure through said roll, a steam supply conduit coupled to said system for heating the water, a valve in said conduit, said system including a vessel connected to the inlet and outlet of said roll and adapted to contain the water to be circulated through the roll, said system including a temperature sensor means for detecting the temperature of the water and controlling said valve, motor means connected to the roll for rotating the roll, and means including said sensor means for maintaining the temperature of said roll as heated by the circulated water at a point so that a starch adhesive bonding agent applied by the roll will be at a temperature about and F. and just below its gelatinization temperature.

2. A system in accordance with claim 1 wherein said system includes a pump for circulating the heated water under pressure through the roll, and circuitry for operating said pump only when said roll is being rotated.

3. A system in accordance with claim 1 including a second applicator roll parallel to said first applicator roll, said system being coupled to said second applicator roll in the same manner that it is coupled to said first-mentioned applicator roll.

4. A system in accordance with claim 3 including a common conduit in said system communicating said vessel with the outlet of each roll.

5. A system in accordance with claim 1 including a A baffle within said roll, said baffle being a sealed hollow structure having tapered ends and supported internally of the roll by spaced ribs.

6. A system in accordance with claim 1 including a corrugator bridge, a frame supporting said system from said bridge.

7. A system in accordance with claim 1 wherein said system includes a pump for circulating the water under pressure through said roll, said pump being located between said vessel and the inlet to said roll. 

1. A system for applying a starch adhesive bonding agent in a paperboard corrugator comprising at least one hollow adhesive applicator roll having an inlet and an outlet, means adjacent the roll for supporting the bonding agent, a closed circulation system for circulating heated water under pressure through said roll, a steam supply conduit coupled to said system for heating the water, a valve in said conduit, said system including a vessel connected to the inlet and outlet of said roll and adapted to contain the water to be circulated through the roll, said system including a temperature sensor means for detecting the temperature of the water and controlling said valve, motor means connected to the roll for rotating the roll, and means including saId sensor means for maintaining the temperature of said roll as heated by the circulated water at a point so that a starch adhesive bonding agent applied by the roll will be at a temperature about 130* and 145*F. and just below its gelatinization temperature.
 2. A system in accordance with claim 1 wherein said system includes a pump for circulating the heated water under pressure through the roll, and circuitry for operating said pump only when said roll is being rotated.
 3. A system in accordance with claim 1 including a second applicator roll parallel to said first applicator roll, said system being coupled to said second applicator roll in the same manner that it is coupled to said first-mentioned applicator roll.
 4. A system in accordance with claim 3 including a common conduit in said system communicating said vessel with the outlet of each roll.
 5. A system in accordance with claim 1 including a baffle within said roll, said baffle being a sealed hollow structure having tapered ends and supported internally of the roll by spaced ribs.
 6. A system in accordance with claim 1 including a corrugator bridge, a frame supporting said system from said bridge.
 7. A system in accordance with claim 1 wherein said system includes a pump for circulating the water under pressure through said roll, said pump being located between said vessel and the inlet to said roll. 